Research studies reveal that students need to be able to automatically recognize a large amount of words in order to comprehend texts. This chapter highlights the high-frequency words that make up 90% of words in fiction and nonfiction. The appendix includes the different word lists that all students should automatically recognize. The chapter then discusses what teachers should know when teaching high-frequency words lists. The Common Core State Standards Foundational Skills that include word recognition are listed. The “Assessment” section explains types of formal and informal word recognition assessments. The “Intervention” section describes activities emphasizing receptive and expressive vocabularies, sight words, sight vocabulary, context clues, analysis of monosyllabic and polysyllabic words, and structural analysis. The “Technology” section lists apps and websites teachers can use to enhance students’ word recognition skills. The chapter begins and ends with two different classroom scenarios with guiding and reflective questions that can be used for classroom discussions.